Showing papers presented at "International Conference on Mobile Networks and Management in 2015"

Analysis of Group-Based Communication in WhatsApp

Abstract: This work investigates group-based communication in WhatsApp based on a survey and the analysis of messaging logs. The characteristics of WhatsApp group chats in terms of usage and topics are outlined. We present a classification based on the topic of the group and classify anonymized messaging logs based on message statistics. Finally, we model WhatsApp group communication with a semi-Markov process, which can be used to generate network traffic similar to real messaging logs.

A Novel Data Dissemination Model for Organic Data Flows

Abstract: The number of computing devices of the IoT are expected to grow exponentially. To address the communication needs of the IoT, research is being done to develop new networking architectures and to extend existing architectures. An area that lacks attention in these efforts is the emphasis on utilisation of omnipresent local data. There are a number of issues (e.g., underutilisation of local resources and dependence on cloud based data) that need to be addressed to exploit the benefits of utilising local data. We present a novel data dissemination model, called the Organic Data Dissemination (ODD) model to utilise the omni-present data around us, where devices deployed with the ODD model are able to operate even without the existence of networking infrastructure. The realisation of the ODD model requires innovations in many different area including the areas of opportunistic communications, naming of information, direct peer-to-peer communications and reinforcement learning. This paper focuses on highlighting the usage of the ODD model in real application scenarios and the details of the architectural components.

Radio-Aware Service-Level Scheduling to Minimize Downlink Traffic Delay Through Mobile Edge Computing

Abstract: One of the most challenging problems in mobile broadband networks is how to assign the available radio resources among the different mobile users. Traditionally, research proposals are either specific to some type of traffic or deal with computationally intensive algorithms aimed at optimizing the delivery of general purpose traffic. Consequently, commercial networks do not incorporate these mechanisms due to the limited hardware resources at the mobile edge. Emerging 5G architectures introduce cloud computing principles to add flexible computational resources to Radio Access Networks. This paper makes use of the Mobile Edge Computing concepts to introduce a new element, denoted as Mobile Edge Scheduler, aimed at minimizing the mean delay of general traffic flows in the LTE downlink. This element runs close to the eNodeB element and implements a novel flow-aware and channel-aware scheduling policy in order to accommodate the transmissions to the available channel quality of end users.

The Presidium of Wireless Sensor Networks - A Software Defined Wireless Sensor Network Architecture

Abstract: Software Defined Networking (SDN) is emerging as a key technology to deal with the ever increasing network management burden created by our increasingly interconnected world. Wireless sensor network (WSN) are part of this interconnection, enabling to connect the physical world to the cyber world of the Internet and its networks. This connection of physical items, “Things”, to the Internet in the form of an Internet of Things is creating many new challenges for the management of the Internet networks. SDN moves away from a distributed management approach that has been at the core of wireless sensor networks since their inception and introduces a centralised view and control of a network. We believe that the SDN concept as well as the general compute virtualisation enabled through infrastructure as a service can offer the required flexible management and control of the network of Things. While the application of SDN to WSN has already been proposed, a comprehensive architecture for Software Defined Wireless Sensor Networks (SD-WSN) is currently missing. This paper provides a survey of related work considering both SDN and centralised non-SDN approaches to network management and control, examines the challenges and opportunities for SD-WSNs, and provides an architectural proposal for SD-WSN.

A Scoring Method for the Verification of Configuration Changes in Self-Organizing Networks

Abstract: In today’s mobile communication networks the increasing reliance on Self-Organizing Network(SON) features to perform the correct optimization tasks adds a new set of challenges. In a SON-enabled network, the impact of each function’s action on the environment depends upon the actions of other functions as well. Therefore, the concept of pre-action coordination has been introduced to detect and resolve known conflicts between SON function instances. Furthermore, the idea of post-action SON verification has been proposed which is often understood as a special type of anomaly detection. It computes statistical measures on performance indicators at a relevant spatial and temporal aggregation level to assess the impact of a set of (SON-evoked) Configuration Management (CM) changes.

FESTIVAL: Towards an Intercontinental Federation Approach

Abstract: In the last years, in both Europe and Japan, several initiatives have been started with the aim of building and testing Internet of Things and Smart ICT architectures and platforms to address specific domain issues through designed solutions. FESTIVAL EU-Japan collaborative project aims at federating these testbeds, making them interoperable, allowing centralized data collection and analyzing societal issues in both cultures, all of it under a user privacy-preserving context. In this sense, FESTIVAL pursues a twofold approach: firstly, the intercontinental federation of testbeds in Japan and Europe using existing tools as well as developing new ones; and secondly, the creation of new services and experiments, to be performed on top of the FESTIVAL testbeds and experimentation facilities, associated to three different smart city domains: smart energy, smart building and smart shopping. Throughout this article the current status of the project (in its first year) is shown, describing the Experimentation as a Service federation approach to be implemented, with a first analysis of the platforms and testbeds that are included within the project. Furthermore, the paper also describes the services and use cases that will be conducted within FESTIVAL lifespan. Finally, next steps to be carried out in the coming years of the project are indicated.

Energy Considerations for WiFi Offloading of Video Streaming

Abstract: The load on cellular networks is constantly increasing. Especially video streaming applications, whose demands and requirements keep growing, put high loads on cellular networks. A solution to mitigate the cellular load in urban environments is offloading mobile connections to WiFi access points, which is followed by many providers recently. Because of the large number of mobile users and devices there is also a high potential to save energy by WiFi offloading. In this work, we develop a model to assess the energy consumption of mobile devices during video sessions. We evaluate the potential of WiFi offloading in an urban environment and the implications of offloading connections on energy consumption of mobile devices. Our results show that, although WiFi is more energy efficient than 3G and 4G for equal data rates, the energy consumption increases with the amount of connections offloaded to WiFi, due to poor data rates obtained for WiFi in the streets. This suggests further deployment of WiFi access points or WiFi sharing incentives to increase data rates for WiFi and energy efficiency of mobile access.

On the Use of Emulation Techniques over the ns-3 Platform to Analyze Multimedia Service QoS

Abstract: This paper presents an assessment study on the use of emulation techniques to evaluate the performance of multimedia services, in particular a video streaming application. The proposed methodology exploits the emulation functionality that has been integrated into the ns-3 simulation platform, as well as virtualization techniques. We describe the requirements and the main limitations of the scheme, in order to offer an appropriate accuracy. Last, and in order to assess the feasibility of the proposed scheme and its potential, we carry out a study of various QoS parameters of a video streaming application.

A Predictive Model for Minimising Power Usage in Radio Access Networks

Abstract: In radio access networks traffic load varies greatly both spatially and temporally. However, resource usage of Base Stations (BSs) does not solely depend on the traffic load; auxiliary devices contribute to resource usage in a load invariant manner. Consequently, BSs suffer from a large underutilisation of resources throughout most of the day due to their optimisation for peak traffic hours. In this paper an energy saving scheme is proposed with the use of an Artificial Neural Network (ANN) predictive model to make switching decisions ahead of time. The optimum set of BS to turn off while maintaining Quality Of Service (QoS) is formulated as a binary integer programming problem. We validated our model and found large potential savings using an extensive data set spanning all network usage for three months and over one thousand BSs covering the entirety of Dublin city and county.

Using an Identity Plane for Adapting Network Behavior to User and Service Requirements

Abstract: The advent of Software Defined Networking (SDN) has opened the door to new network functions that were difficult or even impossible to have. This has been the case of typically complex network management operations, which now can be layered on top of SDN controllers in order to adapt network behavior to achieve some objectives or quickly react to network events so network consistence is unaltered by them. However, users and services have little to say in current SDN architectures. In this paper we discuss how to use an Identity Plane to carry user and service identities and requirements to network controllers, which would contact a management service that follows the management model proposed by Autonomic Computing (AC) to know the necessary changes to adapt the network behavior to such requirements.

A Framework for Cell-Association Auto Configuration of Network Functions in Cellular Networks

Abstract: Self-Organizing Networks (SONs) introduce automation in Network Management (NM). Herein, SON functions automate the traditional NM tasks in the network. For some of these tasks, several cells must be associated together in order to achieve the intended objectives. As such, part of the process of configuring SON function is the configuration or selection of the required cell associations. For end-to-end automated NM, it is necessary that this task is also automated, especially in an environment with many SON functions.

The Shared Spectrum Service, Technology and Network Provision in Mobile Communication

Abstract: This text describes some developments of an explosive growth in mobile traffic demand. The growth has led to market driven approaches and need for more effective spectrum access and management. Regulatory, technology and economic issues have led to innovative strategic approaches and policies for more effective spectrum usages. This text seeks factors and possibilities to influence spectrum sharing and use of additional spectrum in mobile communication. Wireless network architecture defines functionalities, which impact on mobile subscriber’s behavior both technically and economically. If telecommunication services fit together, interfaces between elements and services are the key. Economic assets form a new shared spectrum access, which means ubiquitous technical functionality, new service architectures and interfaces between different radio networks in the value-added chains. The modern radio networks form bit-pipes for added value services. For different stakeholders there are technology environment, economic environment and content wish environment in search for additional spectrum utility.

Algorithms for Theoretical Investigation of Fairness in Multipath Transport

Abstract: With the onset of multipath transport protocols such as MPTCP and multihomed mobile devices, fairness considerations which have been widely analyzed for legacy TCP need to be re-investigated. A practical realization of fairness amongst different participants is known to be difficult but even the theoretical calculation of the resource capacity and its allocation is not a trivial task. Therefore in this work, resource allocation algorithms are presented to thoroughly evaluate the impact of the fairness definitions. For a rigorous analysis, existing fairness definitions are identified according to the resources (bottleneck or network) and the competing participants (flow, tariff or user). Tariff as the participant, provides a realistic option to comply with the service level agreement between the operator and the user where as flow as the participant leads to TCP-compatible allocation. From the obtained results, it can be seen that if fairness is applied at the bottleneck then it is absolutely fair to the individual participants w.r.t. the bottleneck. On the other hand, fairness mechanisms considering the whole network as a single resource exploit the freedom of resource allocation (due to multipath flows) to achieve an overall similar allocation for the different participants (irrespective if the participant is composed of singlepath or multipath flows) but are still restricted by the topological constraints and might even result in a lower overall network throughput (This work has been funded by the German Research Foundation (Deutsche Forschungsgemeinschaft – DFG)).

Alarm Prioritization and Diagnosis for Cellular Networks

Abstract: Alarm events occurring in telecommunication networks can be an invaluable tool for network operators. However, given the size and complexity of today’s networks, handling of alarm events represents a challenge in itself, due to two key aspects: high volume and lack of descriptiveness. The latter derives from the fact that not all alarm events report the actual source of failure. A failure in a higher-level managed object could result in alarm events observed on its controlled objects. In addition, alarm events may not be indicative of network distress, as many devices have automatic fallback solutions that may permit normal network operation to continue. Indeed, given the amount of equipment in a network, there can be a “normal” amount of failure that occurs on a regular basis; if each alarm is treated with equal attention, the volume can quickly become untenable. To address these shortcomings, we propose a novel framework that prioritizes and diagnoses alarm events. We rely on a priori information about the managed network structure, relationships, and fault management practices, and use a probabilistic logic engine that allows evidence and rules to be encoded as sentences in first order logic. Our work, tested using real cellular network data, achieves a significant reduction in the amount of analyzed objects in the network by combining alarms into sub-graphs and prioritizing them, and offers the most probable diagnosis outcome.

On the Performance of Indoor Ultra-Dense Networks for Millimetre-Wave Cellular Systems

Abstract: The combination of Ultra-Dense Networks (UDN) and millimetre Waves (mmW) communications has recently been recognized by the industry and research community as a promising solution to cope with the evolving requirements of the fifth generation (5G) of cellular networks. Indeed, the problem of capacity provisioning has drawn the attention to mmW due to the spectrum scarcity at lower frequency bands. Additionally, the densification process has already started with the introduction of the well-known Heterogeneous Networks (HetNets).Thus the use of UDN is another natural approach for increasing the overall network capacity, especially in such indoor environments where high data rates and service demand are expected. In this paper, the combination of the previous paradigms is analysed by means of comprehensive system-level simulations. Unfortunately, the particularities of indoor deployments make radio propagation difficult to predict and limit the macro-cell coverage, hence these simulations have been evaluated using advanced Ray Tracing (RT) techniques. Results confirm the superior system performance of the mmW and UDN tandem with respect to current operating bands.

A Context-Aware Method Decoupled from Protocol for Adapting Routing Process in DTN

Abstract: Several routing protocols for Delay-Tolerant Networks (DTNs) can be found in the literature. All these protocols have strengths and weaknesses depending on the usage scenario. Nevertheless, in DTNs, messages are forwarded hop-by-hop autonomously, without an on-line path connecting the source and the destination. This unique characteristic of DTNs allows the routing protocol to be changed on-the-fly while a message traverses the network. The only limitation is that each pair of nodes must share the same routing protocol. If each node is able to choose the best routing protocol based on its context and on the available routing protocols, it is possible to minimize the weaknesses of the chosen protocols. In this way, this article proposes an on-the-fly context-aware routing adaptation method. Each node, independently, chooses the routing protocol to forward a message, based on its own context information and on the routing protocols available at the possible next hops. Thus, in order to explore the strengths of all protocols and reduce their weaknesses, every message can be forwarded from the source to the destination through several different routing protocols, one for each hop if necessary. The feasibility and the efficiency of the proposed method are evaluated through simulations, and the results demonstrate that it is possible to increase the delivery ratio and reduce the delay with a small increase on the overhead.

Optimal Uplink Scheduling for Device-to-Device Communication with Mode Selection

Abstract: Device-to-Device communication is discussed for future mobile communication systems. In this work, an upper bound capacity limit is determined for a mobile communication system consisting of Device-to-Device and cellular users is determined. Therefore, we formulate the problem as a linear program and solve it optimally. The potential of Device-to-Device communication is evaluated using a distance based mode selection scheme. It is shown that the amount of traditional cellular users is influencing the optimal distance for using Device-to-Device communication instead of traditional cellular transmission. The optimisation potential is then analysed for a different amount of users and cell sizes.

Lightweight random linear coding over wireless mesh networks

Abstract: We propose an enhanced version of an intra-flow Network Coding protocol, which was conceived to offer a reliable communication service, by means of the combination a Random Linear Coding (RLC) scheme with the UDP protocol. We reduce the overhead that was originally required in the protocol header and we assess, through an extensive campaign carried out over the ns-3 framework, the performance gain that is brought by this enhancement, comparing it to the TCP protocol, as the mainstream transport-level solution to offer a reliable service. We study the impact of the various configuration parameters of the solution. Afterwards, we challenge the proposed scheme over random topologies (Wireless Mesh Networks or WMNs). The results show a remarkable gain (approximately 20 times higher) of the performance over an ideal channel, thanks to the aforementioned overhead reduction.

Making HeNB More Secure with Improved Secure Access Protocol and Analyzing It

Abstract: The 3rd Generation Partnership Project (3GPP) defined a new architecture, called Home eNode B (HeNB). HeNB is able to provide new services with higher data rate in a low cost. Security is a critical aspect of HeNB. In order to have HeNB secure access to core network, 3GPP defines an authentication protocol based on IKEv2. A number of security vulnerabilities such as HeNB masquerading have not been addressed and solved by 3GPP technical specification yet. In this paper an improved HeNB authentication protocol is introduced which does not allow an attacker to connect unauthorized network users using a mask. Finally, we evaluate our protocol performance and verify it by Automated Validation of Internet Security Protocols and Applications (AVISPA). Through our security analysis, we conclude that not only the proposed protocol prevents the various security threats but also it has no significant effect on authentication delay and cost.

Exposure Assessment in Heterogeneous Networks Accounting for up- and Downlinks

Abstract: EMF exposure of people induced by both base station antennas and mobile terminal devices, in a heterogeneous network environment, in a given area, is addressed in this paper. The Specific Absorption Rate (SAR) and the Exposure Index (EI) are used to evaluate exposure, which takes multiple systems, users, postures, and usage profiles into account, among other aspects. One analyses the exposure in heterogeneous networks, consisting of GSM, UTMS, LTE and WLAN systems, for multiple usage scenarios. By using full systems simulations and exposure models, one estimates the EI for several conditions. The use of power control has a major impact on the SAR a person is exposed to. It is verified that, for the scenario under analysis, the uplink power of users’ own terminal contributes to more than 90 % to the overall SAR.

Analyzing the Impact of Delay and Packet Loss on Google Docs

Abstract: Software as a Service allows end users to use complex software directly from their browsers, transferring heavy computation to servers in the cloud. One use of this paradigm is word processing, former a classic use cases of Thin-Client computing. Similar to Thin-Clint systems, the network parameters are an important influence factor for the cloud application performance.